AMERICAN INDUSTRIES SINCE COLUMBUS. 189 



the finishing the processes in which the mechanical advance has 

 been fundamental. The various machines which now expedite the 

 supplementary processes have grown out of the inventions which 

 have attended these fundamental processes, and they are of special 

 interest only to those practically engaged in the manufacture. 

 Their invention has been suggested in fact, compelled by im- 

 provements in the primary machinery. We shall be struck, as 

 we proceed, with the dependence of each forward step in this 

 evolution upon some preceding advance, one invention making 

 possible others, which without it would not have been dreamed of. 



The wool comes into the mill dirty, greasy, burry, sometimes 

 washed by the farmer, but generally just as it is sheared from the 

 sheep, a filthy and unwholesome thing, giving little sign of the 

 beautiful white and flossy substance into which it is soon con- 

 verted. It must first be sorted, each fleece containing from six to 

 eight qualities of sorts, which the careful manufacturer separates, 

 devoting each quality to the purpose for which it is best suited. 

 No skill in carding, spinning, weaving, or finishing, can possibly 

 produce a soft or fine piece of goods from a coarse, hard fiber. 

 When a woolen thread is to be spun to the length of 15,360 yards 

 to a pound, or in the case of a worsted thread to twice that num- 

 ber of yards to a pound, everything depends upon care in the 

 selection of the fleece and in the sorting. These sorts are impreg- 

 nated with a greasy substance called the yolk or suint, caused by 

 the animal secretions and the perspiration of the skin, a com- 

 pound of potash and animal fat, which must be completely eradi- 

 cated. The elimination of the yolk, dirt, and foreign substances, 

 common to all wools, results in a shrinkage of from fifty to 

 seventy per cent. 



Our ancestors scoured their wool in tubs, much as our wives 

 and daughters scour our clothes to-day. In the hand-washing of 

 wool, a tub was filled with the suds, in which one or two men 

 with long poles stirred the wool until clean, when they lifted it 

 upon a traveling apron, which carried it between a pair of rollers 

 which squeezed out the water. The same principle is applied 

 in the automatic scouring now in vogue. Great forks or rakes 

 seize the wool as it is carried by rollers from a feeding apron into 

 the iron tanks, and by alternating motions of their teeth give it 

 a thorough scouring. Thus cleansed, the wool is delivered by 

 rollers to the drying machines, where hot air and great fans are 

 now utilized to extract all the moisture without tearing the fiber. 

 The ventilation drying of wool by means of hot air effects the 

 object in one tenth of the time occupied by the old method of 

 drying by exposure in the open air. So enormous has been the 

 increase in the production of wool, stimulated in all quarters of 

 the globe by the enlarged capacity for its manufacture ; so different 



